Fountain mathematical drawing pen for india ink



June 25, 1929.

F. G. L. ALLEN ET AL FOUNTAIN MATHEMATICAL DRAWING PEN FOR INDIA INK Filed Sept. '7, 1927 q A z. 0 Emuun? 45 U E C. Bel [Jew Patented June 25, 1929.

Uhil'l'tl dTA'lES PATENT OFFICE.

FREDERICK GEORGE LESLIE ALLEN AND EDWIN COBIVEACK BENDER, OF SYDNEY, NEW

SOUTH WALES, AUSTRALIA.

FGIIITIAIN MATHEMATICAL DRAWING PEN FOR INDIA INK.

Application filed September This invention relates to mathematical drawing pens of the type in which is embodied a reservoir of india ink or the like which is allowed to feed to the point of the pen as a required.

The object of the invention is to provlde a simple and inexpensive pen of this type from which a continuous flow of ink may be maintained by means of capillary action and which 10 shall be capable of easy and accurate control.

The invention will now be described with reference to the accompanying drawings in which a pen constructed according to the invention is illustrated and in which Figure l is a perspective view of the lower part of the complete pen,

Figure 2 is a sectional perspective the pen,

Figure 3 is a perspective view of feeding tube.

Figure 4 is a sectional perspective the lower end of the barrel,

Figure 5 is a sectional elevation of the pen blades, and

Figure 6 is an enlarged perspective view of the lower end of the ink tube.

The barrel 7 consists of a tube of ebonite or any other well known and suitable non-corrosive material into whit-n ink may be inserted by unscrewing the plug 8.

The head of the pen consists of the plug 8 which is provided with pen blades 9 of a type usually employed in matheiuatical drawing pens and which may be hollow ground or flat and either formed in one piece or formed separately and connected to the plug 8 in any suitable manner.

An ink tube 10 passes through the body of the plug 8 to within about one quarter an 0 inch of the end of the blades and is provided with an ink pin 11 which has two or more grooves 12 formed in it and running its full length. The upper end of this pin is provided with an adjustable nut 13 against which the compression spring 14: bears, the other end of the spring bearing in the loose tube 15 which acts as a chamber to collect sediment in the ink.

The lower end of the ink pin 11 is flattened view of the ink view of 7, 1927. Serial No. 218,082.

as shown and is provided with an arm 16 which projects through the slot 17 and from between the blades 9 to the side of the pen. A finger grip 18 is provided at the end of the arm.

In use, ink is caused to flow from the bar rel 7 through the tube 10 to between the blades 9 by operating the pin 11 by means of the tinger grip 18. As the ink is used the supply to the point of the pen will be maintained by capillary action through the grooves 12 the supply being augmented if necessary by occasional operation of the ink pin 11.

The distance between the blades may be regulated by the nut 19 on to threaded bar 20 which is attached to the ring 21 surrounding the ink tube 10 and any well known device may be used for forcing the blades apart.

The length and travel. of the ink pin 11 are so adjusted that it may be projected between the points of the blades 9 to remove any solidified ink and the arm 16 is guided by the bracket 22.

The barrel 7 may be replaced by any well known self filling reservoir arrangement from which ink may be conveyed to the ink tube 10 and a cap may be provided to fit over the end of the ink tube and blades when the pen not in use.

The various parts may be constructed. of any Well known non-corrosive nuiterials and various minor modilicatious may be made in the design of the parts without exceeding the scope of this description.

Vi e claim A fountain mathematical drawing pen comprising a head, a barrel connected to the head, pen blades also connected to the head one of which is adjustable, an ink supply tube arranged through the head and projecting within a short distance of the ends of the blades and also projecting slightly within the barrel, a sediment chamber arranged about the tube within the barrel and adjacent the head, a longitudinally grooved ink pin slidably arranged in the tube and projecting beyond the ends thereof, a coiled spring arranged about that portion of the tube within the barrel, means for adjusting the tension of the spring, an apertured bracket on the the use thereof substantially as and for the head and an upwardly extending arm integral purposes set forth.

with the outer end of the pin and sliclable In testimony whereof we have aflixed our 1 through the bracket and having a finger porsignatures.

. 5 tion positioned in proximity to the barrel whereby the flow of ink through the tube may FREDERI K EOR E LESLIE ALLEN. be accelerated by the user of the pm during EDWIN C RMACK BENDER. 

